FrazerJames Posted August 10, 2020 Share Posted August 10, 2020 I nearly posted this in my previous thread, but it ended up being mostly a conversation about whether EFI is an actual upgrade or not. Super informative, but I thought it be a hard turn to jump to this. As explained previously, I’m planning to upgrade the 83 Bronco with the 3G alternator, Saginaw PS, Effy C intake manifold and the Holley Sniper EFI system in that order. I’ll be using much of what’s provided on this site to guide me, so, THANK YOU! Here’s my question: The PO had disabled the EGR system, but that seems to have created some vacuum issues (as suggested by very high idle with my existing Carter Carb). As I’m prioritizing all those projects and eyeing how I’m going to go about them, I can’t help but notice this big pump in my way of replacing the alternator. I believe this is the “smog pump”? Or is that just a regular vacuum pump? Either way, if I’m moving to EFI, do I really need that thing? The EGR has supposedly been “disabled” as mentioned before, but I’m pretty sure I still see it attached to the block. I’m guessing if I remove the pump, block off all the vacuum hoses, remove the EGR and replace it with a block, it won’t detriment the engine? My only concern is that I was in the dash and noted some vacuum lines (maybe for the AC?). Just need some guidance here. I’d love to clean up the engine bay a bit. I also read a thread on here about someone using that second pulley on the Alt to double up belts - I wouldn’t mind doing that if possible... Link to comment Share on other sites More sharing options...
Rusty_S85 Posted August 10, 2020 Share Posted August 10, 2020 that is the air pump, it injects air into the exhaust to help your converter burn HC that is still in the exhaust. Thing with the sniper is they strongly suggest you do not retain emission systems. You can retain some but I dont believe they recommend keeping converters and air pumps especially since you are pumping air into the exhaust before your O2 sensor which will make your sniper think it is running lean and richen the fuel up to the point that you are loading the engine up with raw fuel. You honestly dont need that and your EGR you wont need either but without the EGR you should really consider having your distributor advance recurved as the advance curve is put into the distributor with the egr taken into account. The air pump, it can be removed with no problem just remember to plug the air injection ports as you dont want any kind of leaks before your O2 sensor in the exhaust circuit. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 10, 2020 Share Posted August 10, 2020 that is the air pump, it injects air into the exhaust to help your converter burn HC that is still in the exhaust. Thing with the sniper is they strongly suggest you do not retain emission systems. You can retain some but I dont believe they recommend keeping converters and air pumps especially since you are pumping air into the exhaust before your O2 sensor which will make your sniper think it is running lean and richen the fuel up to the point that you are loading the engine up with raw fuel. You honestly dont need that and your EGR you wont need either but without the EGR you should really consider having your distributor advance recurved as the advance curve is put into the distributor with the egr taken into account. The air pump, it can be removed with no problem just remember to plug the air injection ports as you dont want any kind of leaks before your O2 sensor in the exhaust circuit. I'm not disagreeing with Rusty. Just providing a bit more info. As said, the Air Injection Reaction (AIR) pump is there to put additional oxygen in the mix going into the catalytic converter. And with the old style cats you need that. So if you pull the pump or disable it you could have a plugged cat sometime down the road as it won't have enough oxygen to burn all the hydrocarbons. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted August 10, 2020 Share Posted August 10, 2020 I'm not disagreeing with Rusty. Just providing a bit more info. As said, the Air Injection Reaction (AIR) pump is there to put additional oxygen in the mix going into the catalytic converter. And with the old style cats you need that. So if you pull the pump or disable it you could have a plugged cat sometime down the road as it won't have enough oxygen to burn all the hydrocarbons. Correct, but even with the sniper holley strongly recommends not using their EFI with emission systems. Only emission systems I would ever consider using are PCV and EVAP. But catalyst and EGR I wouldnt use. Link to comment Share on other sites More sharing options...
FuzzFace2 Posted August 10, 2020 Share Posted August 10, 2020 Correct, but even with the sniper holley strongly recommends not using their EFI with emission systems. Only emission systems I would ever consider using are PCV and EVAP. But catalyst and EGR I wouldnt use. On MY 300 the AIR goes in just before the CAT that is after the 02 sensor so cant see the issue in running the air pump. I also find it strange that sniper said to remove all the smog stuff as it is not what the law wants you to do and you can be fined and / or go to jail. Just strange is all and yes all my smog is gone This high idle you talk of even if the smog stuff is on or off the motor the idle should be able to be adjusted so look for a vacuum leak somewhere. On the 2 belts for the ALT. What you have now you cant do that. Look at all the belts: belts run from motor out on crank. 1 belt for ALT/water pump/crank 1 belt for PS/water pump/crank 1 belt for AC/water pump/crank 1 belt for ALT/air pump Only non AC motors had 2 belts for the ALT and the air pump ran off the crank IIRC. I just went thru all this when I installed the AC compressor on my motor. Oh my motor never had the air pump on it and I blocked off the EGR but the valve is in place and can hook a vacuum hose to it but it will never work. Yes you do have vacuum hoses to the HVAC control and with out it you could not change air flow from the defrost to floor or vents. Only vacuum you need: carb to dist. and Intake to power brakes & HVAC panel. That is all I have on my truck and it runs great working on getting the MPG up a little bit. Dave ---- Link to comment Share on other sites More sharing options...
FrazerJames Posted August 10, 2020 Author Share Posted August 10, 2020 On MY 300 the AIR goes in just before the CAT that is after the 02 sensor so cant see the issue in running the air pump. I also find it strange that sniper said to remove all the smog stuff as it is not what the law wants you to do and you can be fined and / or go to jail. Just strange is all and yes all my smog is gone This high idle you talk of even if the smog stuff is on or off the motor the idle should be able to be adjusted so look for a vacuum leak somewhere. On the 2 belts for the ALT. What you have now you cant do that. Look at all the belts: belts run from motor out on crank. 1 belt for ALT/water pump/crank 1 belt for PS/water pump/crank 1 belt for AC/water pump/crank 1 belt for ALT/air pump Only non AC motors had 2 belts for the ALT and the air pump ran off the crank IIRC. I just went thru all this when I installed the AC compressor on my motor. Oh my motor never had the air pump on it and I blocked off the EGR but the valve is in place and can hook a vacuum hose to it but it will never work. Yes you do have vacuum hoses to the HVAC control and with out it you could not change air flow from the defrost to floor or vents. Only vacuum you need: carb to dist. and Intake to power brakes & HVAC panel. That is all I have on my truck and it runs great working on getting the MPG up a little bit. Dave ---- Great info Dave! Thanks! If I’m losing the carb and going EFI, what would hook up to the Distrubuter? Jim Link to comment Share on other sites More sharing options...
FuzzFace2 Posted August 10, 2020 Share Posted August 10, 2020 Great info Dave! Thanks! If I’m losing the carb and going EFI, what would hook up to the Distrubuter? Jim Not sure but from what little I have seen posted on after market EFI is you need a dist. that the EFI computer can control. So the stock dist., if it will work, will need to be locked so it cant change the timing. I was talking for now if you wanted to remove the air pump & EGR and any of the vacuum lines & junk you can and just keep what I listed. Dave ---- Link to comment Share on other sites More sharing options...
FrazerJames Posted August 10, 2020 Author Share Posted August 10, 2020 Great info Dave! Thanks! If I’m losing the carb and going EFI, what would hook up to the Distrubuter? Jim Not sure but from what little I have seen posted on after market EFI is you need a dist. that the EFI computer can control. So the stock dist., if it will work, will need to be locked so it cant change the timing. I was talking for now if you wanted to remove the air pump & EGR and any of the vacuum lines & junk you can and just keep what I listed. Dave ---- It sounds like the consultant I’m working with says my distributer should work fine as long as I don’t want to control firing. Maybe a future upgrade? New related question though - I removed the air pump today and I’m staring at a ton of vacuum lines. Where does the vacuum come from? I’m used to an actual vacuum pump in the Merc Diesel. There’s a tree of vacuum lines near the front of the bay which is maybe controlling the vacuum? Long story short I’m struggling to understand where I should be capping. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 10, 2020 Share Posted August 10, 2020 It sounds like the consultant I’m working with says my distributer should work fine as long as I don’t want to control firing. Maybe a future upgrade? New related question though - I removed the air pump today and I’m staring at a ton of vacuum lines. Where does the vacuum come from? I’m used to an actual vacuum pump in the Merc Diesel. There’s a tree of vacuum lines near the front of the bay which is maybe controlling the vacuum? Long story short I’m struggling to understand where I should be capping. See if this helps understand what vacuum systems you need: Documentation/Underhood/Vacuum Systems. Link to comment Share on other sites More sharing options...
FrazerJames Posted August 10, 2020 Author Share Posted August 10, 2020 See if this helps understand what vacuum systems you need: Documentation/Underhood/Vacuum Systems. That does help for sure. I think I have all those identified. I still just can’t figure out what creates the vacuum. Link to comment Share on other sites More sharing options...
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